Direct current bus voltage finite time passive control method based on hybrid energy storage

Abstract

The invention relates to a direct current bus voltage finite time passive control method based on hybrid energy storage. A super-capacitor and a storage battery are taken as a hybrid energy storage system. The super-capacitor and the storage battery are connected with a direct current bus in parallel through own bidirectional DC-DC converters, thereby forming an energy bidirectional loop. A voltage of the direct current bus, a voltage of the super-capacitor, a voltage of the storage battery and an output current signal of the direct current bus, as control parameters, are input in a finite time passive controller, and through operation of the controller, charge / discharge reference currents of the super-capacitor and the storage battery are generated. Reference current signals and current signals of the super-capacitor and the storage battery, as the control parameters, are input in a current adjusting device, through operation, control signals of the bidirectional DC-DC converters are generated, and the control signals are used for controlling charge / discharge of the hybrid energy storage system, thereby suppressing voltage fluctuation of the direct current bus. The voltage quality of the direct current bus is effectively improved; the voltage is enabled to be stable in finite time; and the response speed of the voltage is improved.

Description

technical field [0001] The invention relates to a power control technology, in particular to a limited-time passive control method of a DC bus voltage based on hybrid energy storage. Background technique [0002] In the application of photovoltaic power generation and wind power generation, it is necessary to configure a certain energy storage system to suppress the fluctuation of the output power of renewable energy. It is difficult for a single energy storage element to meet the requirements of high power, frequent charge and discharge, and high energy storage density at the same time. If supercapacitors and batteries are used in combination, the complementary advantages of power-type energy storage and energy-type energy storage can be fully utilized, which can effectively improve the performance of the energy storage system and the ability to suppress bus voltage fluctuations. For hybrid energy storage systems, due to the presence of bidirectional DC-DC converters with ...

AI Technical Summary

Problems solved by technology

[0005] The present invention aims at the problem of slow convergence speed of the DC bus voltage, and proposes a limited-time passive control method for the DC bus voltage based on hybrid energy storage, which improves the stabilization speed of the DC bus voltage

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